This application relates to remotely operated devices for the cleaning of the interior surfaces of enclosed spaces, such as storage tanks, via water or other fluid streams directed at the surface. With further particularity, this invention relates to a remotely operated apparatus especially suitable for the cleaning of storage tanks within vessels, such as ships, boats (including but not limited to oilfield supply boats), and barges, the apparatus requiring only limited human entry into the enclosed space in order to efficiently carry out the cleaning. In addition, the invention is adapted to the cleaning of mud tanks on drilling rigs, and other enclosed areas.